JP2015186787A - Production method of coating film and monitoring system of production method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a production method of a coating film capable of reducing the number of bubbles contained in the coating film and a monitoring system of the production method.SOLUTION: A production method of a coating film is conducted with an adjusted condition based on a drying condition using a mass transfer coefficient kcalculated by a mathematical expression (1): k=D×(Sc/Pr)×h/k(1) and a calculated drying time tcalculated by a mathematical expression (2): t=k×d×μ (2) (where, kis the mass transfer coefficient (m/sec); D is the diffusion coefficient (m/sec) of a solvent in a gas under a dry atmosphere; h is a heat transfer coefficient (J/(mK sec)); kis the thermal conductivity (J/(m K sec)) of the gas under the dry atmosphere; Sc is a Schmidt number; Pr is a Prandtl number; tis the calculated drying time (sec); d is a coating thickness (m); μ is the viscosity (Pa sec) of a coating liquid; and k=(2/9)×10((m Pa))).

Description

  The present invention relates to a coating film manufacturing method and a manufacturing method monitoring system.

Conventionally, air may be mixed into the coating liquid and bubbles may be mixed into the dried coating film in processes such as preparation of the coating liquid, supply of the coating liquid to the coating means, and coating. When the coating liquid is applied to the substrate, bubbles are degassed in the coating liquid preparation process.
For example, in the case of a high-viscosity coating liquid such as an adhesive, it takes a very long time for the bubbles to rise from the inside of the kettle of the paste making apparatus to the gas-liquid interface. Therefore, after preparation of the coating liquid, it is left for a long time to wait for bubbles to escape, or is defoamed using a special defoaming device. For example, Patent Literature 1 describes a bubble removing device that performs degassing by evacuation.

JP-A-9-155105

  However, even when air bubbles are removed from the coating liquid prepared using the air bubble removing device described in Patent Document 1, when the coating liquid is supplied to the coating means or applied, it is newly added. Air may enter. If the coating liquid on the substrate is dried while air is mixed, a coating film in which bubbles are mixed may be produced.

  The objective of this invention is providing the manufacturing method of a coating film which can reduce the number of the bubbles contained in a coating film, and a manufacturing method monitoring system.

The method of manufacturing a coating film according to one embodiment of the present invention, the drying conditions using a mass transfer coefficient k _m, which is calculated by the following equation (1), and the calculated drying time t _i which is calculated by the following equation (2) It is characterized by performing under the coating-film manufacturing conditions adjusted based on these.
^{_{k m = D × (Sc /}} Pr) 0.42 × h / k a ... (1)
t _i = k _i × d × μ (2)

In the formula (1),
k _m is the mass transfer coefficient (unit is m / sec) is,
D is the diffusion coefficient of the solvent in the gas under a dry atmosphere (unit: m ² / sec),
h is a heat transfer coefficient (unit: J / (m ² · K · sec)),
k _a is the thermal conductivity of a gas in a dry atmosphere (unit: J / (m · K · sec)),
Sc is the Schmitt number calculated by the following mathematical formula (3),
Pr is the Prandtl number calculated by the following mathematical formula (4).

In the formula (3),
η is the viscosity of the gas in a dry atmosphere (unit is Pa · sec),
ρ is the density of gas in a dry atmosphere (unit: kg / m ³ )
D is the diffusion coefficient (unit is m ² / sec) of the solvent in the gas in a dry atmosphere.

In the formula (4),
η is the viscosity of the gas in a dry atmosphere (unit is Pa · sec),
c _p is the specific heat of the gas under a dry atmosphere (in, J / (kg · K) ) is,
k _a is the thermal conductivity of a gas in a dry atmosphere (unit: J / (m · K · sec)).
The Schmitt number is represented by a ratio between the kinematic viscosity of the fluid and the diffusion coefficient of the solvent in the fluid, and is a value indicating the ratio between the velocity distribution and the concentration distribution in the fluid. The Prandtl number is represented by a ratio between the kinematic viscosity of the fluid and the thermal diffusivity, and is a value indicating the ratio between the velocity distribution and the temperature distribution in the fluid.

In the formula (2),
t _i is the calculated drying time (unit: sec),
d is the coating thickness (unit is m);
μ is the viscosity of the coating liquid (unit is Pa · sec),
k _i = (2/9) × 10 ⁶ (the unit is (m · Pa) ⁻¹ ).

A manufacturing method monitoring system according to one aspect of the present invention is a manufacturing method monitoring system for monitoring a manufacturing process of a coating film having a coating means and a drying means, and includes a defect detection means for detecting a defect in the coating film, A discrimination means for comparing the threshold value relating to the stored defect with the information relating to the defect detected by the defect detection means, and the discrimination means determining that the detected defect has exceeded the threshold value The second coating film manufacturing conditions not exceeding the threshold value are calculated and changed from the first coating film manufacturing conditions stored in advance to the second coating film manufacturing conditions, thereby manufacturing the coating film. and a control means for controlling the process, and the coating film production conditions, and drying conditions using the substance transfer coefficient k _m calculated the in equation (1), calculated dry calculated the in equation (2) and time _{t i,} in based Characterized in that it is a condition adjusted Te.

According to the manufacturing method of the coating film according to one embodiment of the present invention, the coating film manufacturing conditions, the drying conditions using a mass transfer coefficient k _m, which is calculated by Equation (1), calculates the in Equation (2) and calculating the drying time t _i to be is adjusted based on. Specifically, to set the drying conditions so as to satisfy a predetermined mass transfer coefficient k _m, and sets the calculated drying time t actual drying time according to _i, the production of the coating is carried out in the dry conditions . As a result, even if air bubbles are mixed in the applied coating liquid, the air bubbles easily escape from the coating liquid. Therefore, according to the coating film manufacturing method of one embodiment of the present invention, the number of bubbles contained in the coating film can be reduced.

  According to the manufacturing method monitoring system according to one aspect of the present invention, when a defect in the coating film is detected by the defect detection unit, the determination unit determines whether or not the threshold value regarding the defect is exceeded, and the threshold value is exceeded. First, the control means changes the second coating film manufacturing condition so as not to exceed the threshold value. This second coating film manufacturing condition is adjusted based on the same formulas (1) and (2) as those in the coating film manufacturing method according to one aspect of the present invention. As a result, according to the manufacturing method monitoring system according to one aspect of the present invention, the number of bubbles contained in the coating film can be reduced, and further, the manufacturing process of the coating film can be appropriately managed.

It is the schematic of the manufacturing apparatus which enforces the manufacturing method of the coating film which concerns on one Embodiment of this invention. It is a cross-sectional schematic diagram showing the internal shape of the drying means which the said manufacturing apparatus has. It is a cross-sectional schematic showing the relationship between the effective width | variety of the said drying means, and the application | coating width | variety of a coating liquid. It is a block diagram which shows the structure of the manufacturing method monitoring system which concerns on one Embodiment of this invention. It is a graph which shows the relationship between the number of the faults in the coating film which concerns on one experimental example of this invention, and drying time.

  Hereinafter, the present invention will be described with reference to embodiments. The present invention is not limited to the contents of the embodiment.

FIG. 1 shows a schematic diagram of a coating film manufacturing apparatus 100 according to an embodiment of the present invention.
The coating film manufacturing apparatus 100 is an apparatus capable of manufacturing the coating film 11 by applying a coating liquid to the long substrate 10 and drying the coating liquid.
The coating film manufacturing apparatus 100 includes a first supply means 30 for feeding out the substrate 10, a coating means 40 for applying the coating liquid 41, a drying means 50 for drying the coating liquid, a manufacturing method monitoring system 20, The 2nd supply means 60 which pays out the protective film 12, the bonding part 70 which bonds the protective film 12 to the coating film 11, and the winding means 80 which winds up the laminated body 1 with the protective film 12 are provided.

  The first supply means 30 includes a rotation motor 31 as a drive device, and a support roller 32 that is rotatably provided by the rotation motor 31. The support roller 32 supports the long base material 10 wound in a roll shape. The base material 10 fed out from the support roller 32 is supplied to the coating means 40 while being guided in the conveyance direction by a guide roller.

The base material 10 in this embodiment is formed with an adhesive layer that is a coating film 11 and supports the coating film 11. The material of the substrate 10 is not particularly limited. For example, polyvinyl chloride resin, polyester resin (polyethylene terephthalate, etc.), acrylic resin, polycarbonate resin, polyethylene resin, polypropylene resin, acrylonitrile / butadiene / styrene resin, Use synthetic resin films such as polyimide resin, polyurethane resin, polystyrene resin, paper materials such as high-quality paper, impregnated paper, glassine paper, coated paper, sheet materials such as nonwoven fabric, wood and metal foil, and plate-like materials it can. A release agent may be applied to the sheet material as necessary, and as the release agent, a silicone resin, a fluororesin, a long-chain alkyl resin, or the like can be used. The shape of the substrate 10 is not particularly limited, but a rectangular shape such as a square or a rectangle, a polygonal shape such as a triangle, pentagon, or hexagon, a circular shape, an elliptical shape, an indefinite shape, a long roll shape, or the like. Various selections may be made depending on the use of the final product. In the present embodiment, an example in which an adhesive layer as a coating film 11 is laminated on a long base material 10 will be described as an example.
The thickness of the substrate is preferably 3 μm or more and 5 mm or less, more preferably 5 μm or more and 3 mm or less, and particularly preferably 10 μm or more and 1 mm or less. If the thickness of the base material is less than 3 μm, the heat resistance and tensile strength are inferior because it is thin, and there is a risk of stretching or breaking due to heat treatment or tension in the lamination process. It may be inferior to handling in When the thickness of the substrate exceeds 5 mm, the winding diameter is limited by the space of the winding portion of the processing machine when winding in a roll shape because the thickness is large, and the required length cannot be obtained, Since the stiffness of the material is strong and the flexibility is poor, the handling property in the processing process may be hindered or the substrate may not be wound up neatly due to the repulsion of the base material.

In this embodiment, the coating means 40 applies a coating liquid 41 containing a constituent component of an adhesive and a solvent to the substrate 10. The coating means 40 is not particularly limited, and examples thereof include a gravure coater, a knife coater, a roll coater, a die coater, and the like. As the die coater, a straight die or a cross head capable of forming a plurality of layers at once. A die, a flat die, or the like can be used. In the present embodiment, the coating means 40 includes a knife roll 42 and a liquid dam portion 43 that stores the coating liquid 41. The coating liquid 41 is prepared in advance by a paste making apparatus or the like and supplied to the liquid dam portion 43. The coating liquid 41 may be prepared and defoamed with a defoaming apparatus, and then supplied to the liquid dam portion 43.
The material of the pressure-sensitive adhesive is not particularly limited and can be widely applied. For example, rubber-based, acrylic-based, silicone-based, polyester-based, urethane-based pressure-sensitive adhesives can be used. In addition, the kind of adhesive is selected in consideration of the use, the kind of adherend to be attached, and the like.
The coating thickness of the coating liquid 41 is not particularly limited, and is appropriately set according to the desired adhesive property in the laminate 1 and the thickness of the adhesive layer as the coating film 11.

The drying unit 50 dries and removes the solvent contained in the coating liquid 41 having a predetermined width applied by the coating unit 40. By removing the solvent, the laminate 1 in which the adhesive layer as the coating film 11 is formed on the substrate 10 is obtained.
In the present embodiment, a predetermined interval is provided between the coating unit 40 and the inlet of the drying unit 50, and normal temperature drying is performed before entering the inside of the drying unit 50.
The drying means 50 may be constituted by one drying chamber, or may be divided into a plurality of drying zones along the conveyance direction of the substrate 10. When the drying means is divided into a plurality of drying zones, the drying conditions can be set for each drying zone.
In the present embodiment, the drying means 50 has six drying zones, and the first drying zone 51, the second drying zone 52, the third drying zone 53, the fourth drying zone 54, and the fifth drying zone in this order from the inlet side. 55 and a sixth drying zone 56. The drying conditions can be set for each of the drying zones 51 to 56. Drying in the drying means 50 is performed in an atmosphere such as an inert gas such as nitrogen, argon, or helium, or air.

FIG. 2 is a schematic cross-sectional view of the drying means 50, and this cross-section is a cross-section in the direction along the conveyance direction of the substrate 10.
Each of the drying zones 51 to 56 of the drying means 50 is provided with a plurality of nozzles 50a for supplying hot air. In the present embodiment, the nozzles 50 a are slit nozzles, and each nozzle 50 a can supply hot air over the width direction of the substrate 10. As shown in FIG. 2, the interval between the nozzles 50a is represented by X (unit is m), and the shortest distance from the hot air outlet tip 50b of the nozzle 50a to the substrate 10 is S (unit is m). The width of the hot air outlet 50b (the width in the direction along the conveyance direction of the base material 10) is represented by W (unit is m).

FIG. 3 also shows a schematic cross-sectional view of the drying means 50, and this cross-section is a cross-section in the direction along the width direction of the substrate 10. As described above, the nozzle 50a is a slit nozzle. 3 shows, for the slit nozzle, hot air supplied from the hot air outlet tip 50b and the effective suppliable width (hot air effective width) W _H to the coating liquid, the coating width W _C of the coating liquid The relationship is represented as a schematic cross section. Coating width W _C is smaller than the hot air effective width W _H, it is preferable that hot air to make the coating width is within the range specified supplied. The width of substrate 10 is also smaller than the hot air effective width W _H.

Here, the adjustment method of the manufacturing conditions of a coating film is demonstrated.
In the present embodiment, manufacturing conditions of the coating, and drying conditions using a mass transfer coefficient k _m, which is calculated by the following equation (1), and the calculated drying time t _i which is calculated by the following equation (2), the Adjusted based on. For the calculation of the mass transfer coefficient, reference was made to the document “Martin. H, Advances in Heat Transfer Volume 13, 1977, Pages 1-60”.

^{_{k m = D × (Sc /}} Pr) 0.42 × h / k a ... (1)
t _i = k _i × d × μ (2)

In Equation (1), _{k m} is the mass transfer coefficient (unit is m / sec) is, D is the diffusion coefficient of the solvent in the gas in a dry atmosphere ^(in, m 2 / sec) at Yes, Sc is the Schmitt number calculated by the following formula (3), Pr is the Prandtl number calculated by the following formula (4), and h is the heat transfer coefficient (the unit is J / (m a ^{2 · K · sec)),} k a is the thermal conductivity of the gas in a dry atmosphere (unit is J / (m · K · sec )).

In the mathematical formulas (3) and (4), η is the viscosity of the gas in the dry atmosphere (unit is Pa · sec), and in the mathematical formula (3), ρ is the density of the gas in the dry atmosphere ( unit is kg / ^{m 3),} D is the diffusion coefficient (unit of the solvent in the gas in a dry atmosphere ^is m 2 / sec), the in equation (4), _{c p} is dried gas specific heat of the atmosphere (in, J / (kg · K) ) is, _{k a} is the thermal conductivity of the gas in a dry atmosphere (in, J / (m · K · sec)) is .

In Equation (2), _{t i} is calculated drying time (in, sec) is, d is applied thickness (unit, m) is, mu is the viscosity (unit of the coating liquid, Pa · sec), and k _i is a coefficient, and in this embodiment, k _i = (2/9) × 10 ⁶ (unit: (m · Pa) ⁻¹ ). In addition, application | coating thickness was taken as the value which remove | divided the coating-film thickness after drying by the ratio of the solid content contained in an adhesive.

  The diffusion coefficient D of the solvent in the gas under the dry atmosphere is calculated based on the following mathematical formula (5). Reference was made to the literature “E. N. Fuller, P. D. Schettler, and J. C. Giddings, Ind. Eng. Chem. 58 (5), 19 (1966)” for the calculation of the diffusion coefficient of the solvent.

In Equation (5), T is the temperature of the gas under a dry atmosphere (unit is K), M _air is the molecular weight of the gas under the dry atmosphere (unit is kg / mol), and M _solvent Is the molecular weight of the solvent (unit is kg / mol), P is the pressure (unit is atm), and V _air is the molar volume of gas under dry atmosphere (unit is m ³ / mol) _Vsolvent is the molar volume of the solvent (unit is m ³ / mol). Under atmospheric pressure, P is 1 atm.
In this embodiment, the diffusion coefficient D of the solvent in the gas in the dry atmosphere is the average value of the diffusion coefficients in each drying zone of the drying means 50. Moreover, when the solvent is a mixed solvent formed by mixing a plurality of types of solvents, the diffusion coefficient D of the mixed solvent is an average value of the diffusion coefficients of the respective solvents.

  The aforementioned heat transfer coefficient h is calculated based on the following mathematical formula (6).

In the formula (6),
k _a is the thermal conductivity of a gas in a dry atmosphere (unit: J / (m · K · sec)),
W is the width (unit is m) of the hot air outlet tip 50b,
Pr is the Prandtl number,
Re is the Reynolds number of the hot air blown from the hot air outlet 50b.
F ₀ is calculated based on the following formula (7),
F is calculated based on the following mathematical formula (8).

      F = W / X (8)

In the formula (7),
S is the shortest distance from the hot air outlet 50b to the base material 10 (unit is m),
W is the width (unit is m) of the hot air outlet tip 50b,
In the formula (8),
X is an interval between nozzles 50a (unit is m),
W is the width of the hot air outlet 50b (unit: m).

  The Reynolds number Re in the equation (6) is calculated based on the following equation (9).

In the formula (9),
ρ is the density of gas in a dry atmosphere (unit: kg / m ³ )
V is the wind speed (unit: m / sec) of the hot air blown from the hot air outlet tip 50b.
W is the width (unit is m) of the hot air outlet tip 50b,
η is the viscosity of a gas in a dry atmosphere (unit: Pa · sec).

In this embodiment, the mass transfer coefficient _{k m} is under the set drying conditions to ^{2.6 × 10 -2 (m / sec} ) or less, the predetermined successive time, it is preferable that drying is carried out. Mass transfer coefficient _{k m} ^{is, 2.6 × 10 -2 (m /} sec) The following drying conditions, predetermined time immediately after the application of the coating liquid is preferably maintained continuously. Note that mass transfer coefficient k _m, so is set according to the drying means and the coating liquid, and the like numerals exemplified in the present embodiment. Mass transfer coefficient _{k m} is more preferably ^{2.5 × 10 -2 (m / sec} ) or less, and more preferably ^{2.4 × 10 -2 (m / sec} ) or less.
And time _{t R} of the mass transfer coefficient _{k m} from immediately after the application of the coating liquid is kept at ^{2.6 × 10 -2 (m / sec} ) following drying conditions, calculated calculated based the on Equation (2) difference Δt between the drying time t _i is, it is preferable to satisfy the condition represented by the following equation (10), it is more preferable to satisfy the condition represented by the following equation (11), the table by the following mathematical formula (12) Is more preferable, and it is more preferable that the condition represented by the following formula (13) is satisfied. The time _{t R,} in other words, the time from immediately after the application of the coating solution until the mass transfer coefficient _{k m} exceeds ^{2.6 × 10 -2 (m / sec} ). In the present embodiment, after the mass transfer coefficient _{k m} exceeds ^{2.6 × 10 -2 (m / sec} ) , again, the mass transfer coefficient _{k m} is ^{2.6 × 10 -2 (m / sec} ) even returned to the following conditions, the time is not included in the time t _R.

Δt = t _R −t _i ≧ −100 (10)
Δt = t _R −t _i ≧ −60 (11)
Δt = t _R −t _i ≧ −30 (12)
Δt = t _R −t _i ≧ 0 (13)

Therefore, in this embodiment, it is preferable that the time t _R is longer between the drying zones 51 to 56 of the drying means 50 immediately after the application of the coating liquid. The upper limit of the difference Δt is not particularly limited. However, if the time t _R is too long, the production efficiency of the coating film is lowered. Therefore, the difference Δt is appropriately selected from the viewpoint of the occurrence of defects and the production efficiency of the coating film. It is preferable that the upper limit of is set.

FIG. 4 is a block diagram showing the configuration of the manufacturing method monitoring system 20 according to this embodiment.
The manufacturing method monitoring system 20 controls the manufacturing conditions while monitoring the manufacturing status of the coating film. The manufacturing method monitoring system 20 includes defect detection means 21, determination means 22, alarm means 23, and control means 24. In the present embodiment, the manufacturing method monitoring system 20 is disposed on the downstream side of the drying means 50.

The defect detection means 21 detects a defect in the coating film 11. In the present embodiment, bubbles contained in the coating film 11 are detected as defects.
Examples of the defect detection means 21 include a configuration including an imaging means for imaging the coating film 11 and an image processing means capable of analyzing the obtained image and measuring the number of bubbles having a predetermined size or more. As the defect detection means 21, for example, an LSC-4000 series surface inspection apparatus manufactured by MEC Co., Ltd. can be used.
The defect detection means 21 supplies information relating to the detected defect to the determination means 22. The defect detection means 21 may continuously detect defects in the coating film 11 continuously formed on the long substrate 10 in the coating film manufacturing apparatus 100 and supply information to the determination means 22. Alternatively, the defect may be detected every predetermined time and the information may be supplied to the determination unit 22.

  The determination unit 22 is connected to the defect detection unit 21. The determination unit 22 compares the threshold value relating to the defect stored in advance with the information relating to the defect supplied from the defect detection unit 21. Examples of the threshold regarding the defect include the number of bubbles having a predetermined size or more per unit area, the number of bubbles included in the predetermined length range of the substrate 10, and the like. In the present embodiment, the number of bubbles having a predetermined size or more per unit area is set as a threshold for defects. The determination unit 22 may include, for example, a first storage unit, and a threshold value related to a defect can be stored in the first storage unit. The discrimination means 22 is connected to the alarm means 23 and the control means 24 in this embodiment. When the determination unit 22 determines that the number of bubbles has exceeded the threshold value regarding the defect, the determination unit 22 supplies information to that effect to the alarm unit 23 and the control unit 24.

  The alarm unit 23 issues an alarm when information indicating that the number of bubbles exceeds the above-described threshold value is supplied from the determination unit 22. As the warning means 23, for example, an indicator lamp, a buzzer or the like can be cited, and any means may be used as long as it allows the operator of the coating film manufacturing apparatus 100 to recognize that the warning has been issued. The alarm issued by the alarm unit 23 may be manually stopped by the operator, or may be stopped by the determination unit 22 or the control unit 24.

The control unit 24 controls the manufacturing process of the coating film 11 based on the information supplied from the determination unit 22. In the present embodiment, when information indicating that the number of bubbles exceeds the threshold value regarding the defect is supplied from the determination unit 22, the control unit 24 causes the first coating film that is a condition when the threshold value is exceeded. The manufacturing condition is changed to the second coating film manufacturing condition that does not exceed the threshold for defects. The control means 24 calculates the second coating film manufacturing condition based on the aforementioned coating film manufacturing condition adjusting method. The control unit 24 may include, for example, a second storage unit, and the second storage unit includes a first coating film manufacturing condition, a second coating film manufacturing condition, a composition and viscosity of the coating liquid, and a coating thickness. In addition, the film thickness and the like can be stored.
In this embodiment, the control means 24 is connected to the first supply means 30, the coating means 40, the drying means 50, the second supply means 60, and the winding means 80, and the calculated second coating film production. It is preferable to control each means based on conditions. For example, if it is necessary to make the drying time of the coating film longer than the first coating film production conditions, the control unit 24 uses the first supply unit 30, the second supply unit 60, and the winding unit 80 to form the base material. 10 and the supply speed of the protective film 12 and the winding speed may be controlled to be slow. Further, when adjustment of the viscosity of the coating liquid and the coating thickness is necessary, the coating means 40 may be controlled. Further, the control means 24 may control the wind speed of the hot air blown from the hot air outlet tip 50b in the drying means 50, the temperature of the gas in the dry atmosphere, and the like. Furthermore, the first supply unit 30, the coating unit 40, the drying unit 50, the second supply unit 60, and the winding unit 80 may be controlled in a complex manner by the control unit 24.

  The second supply means 60 includes a rotation motor 61 as a drive device, and a support roller 62 provided to be rotatable by the rotation motor 61. The support roller 62 supports the long protective film 12 wound in a roll shape. The protective film 12 fed out from the support roller 62 is supplied to the bonding unit 70.

  The bonding unit 70 includes a first bonding roll 71 on which the laminate 1 is laid and a second bonding roll 72 on which the protective film 12 is laid. Laminate 1 and protective film 12 are pasted together by passing between first laminating roll 71 and second laminating roll 72 to form laminated body 1 with protective film 12. The laminated body 1 with the protective film 12 is guided by the first bonding roll 71 and the second bonding roll 72 to the downstream side where the winding means 80 is disposed.

  The winding means 80 includes a rotation motor 81 as a drive device, and a support roller 82 that is rotatably provided by the rotation motor 81. The support roller 82 supports the laminated body 1 with the long protective film 12 wound in a roll shape.

  The laminated body 1 with the protective film 12 wound in a roll shape is cut into a predetermined shape and a predetermined dimension, and can be used as, for example, an adhesive sheet with the protective film 12. This adhesive sheet is attached to an adherend (first adherend) by peeling off the protective film 12 to expose the coating film 11 made of an adhesive. The base material 10 may be used as a support for the coating film 11 as it is, or the base material 10 is peeled off to expose the coating film 11, and another coating body (second coated body) is applied to the coating film 11 made of an adhesive. You may affix a kimono.

  The manufacturing method of the coating film which concerns on this embodiment is implemented based on the coating-film manufacturing conditions adjusted based on the above-mentioned method. Moreover, the manufacturing method of the coating film which concerns on this embodiment can be implemented using the coating-film manufacturing apparatus 100. FIG.

According to the manufacturing method of the coating film according to the present embodiment, the coating film manufacturing conditions, the drying conditions using a mass transfer coefficient k _m, which is calculated the in Equation (1), is calculated the by Equation (2) and calculating the drying time t _i, it is adjusted based on. Specifically, setting the drying conditions so as to satisfy a predetermined mass transfer coefficient _{k m,} preferably, the drying conditions to the mass transfer coefficient _{k m} becomes ^{2.6 × 10 -2 (m / sec} ) or less Set. Incidentally, by setting the mass transfer coefficient k _m to ^{2.6 × 10 -2 (m / sec} ) or less, the viscosity increase of the coating film due to evaporation of the solvent contained in the coating liquid is suppressed, the coating liquid It is considered that the viscosity resistance when bubbles contained in the gas rise to the gas-liquid interface is reduced.
The mass transfer coefficient _{k m} ^{is, 2.6 × 10 -2 (m /} sec) or less of the time _{t R} is kept in a dry condition, calculated drying time _{t i} which are calculated on the basis of the in equation (2) Drying is performed such that the difference Δt satisfies the equation (10). Since the coating film 11 is manufactured under such dry conditions, the number of bubbles contained in the coating film 11 can be reduced. If the difference Δt satisfies the equation (11), the number of bubbles can be further reduced, and if the equation (12) is satisfied, the number of bubbles can be further reduced, and if the equation (13) is satisfied. The number of bubbles can be further reduced. Note that by setting the time t _R so as to satisfy the equation (10) to (13), the time for the bubbles in the coating rises to the gas-liquid interface by buoyancy be obtained.

  According to the manufacturing method monitoring system 20 according to the present embodiment, the defect detection unit 21 determines whether or not the defect-related threshold value is exceeded while the defect detection unit 21 detects the defect in the coating film 11, and exceeds the threshold value. In the case where it is detected, the control means 24 changes the second coating film manufacturing condition so as not to exceed the threshold value. Since the second coating film production condition is adjusted based on the mathematical formula (1) and the mathematical formula (2), the number of bubbles contained in the coating film 11 can be reduced. The manufacturing process of the film | membrane 11 can be managed appropriately.

  It should be noted that the present invention is not limited to the above-described embodiment, and modifications, improvements, etc. within a scope that can achieve the object of the present invention are included in the present invention.

  In the said embodiment, although the aspect which the coating film to manufacture was mentioned as an example and demonstrated, this invention is not limited to such an aspect. For example, examples of the coating film include a hard coat layer, a surface protective layer, an ink receiving layer, and an ink printing layer.

  In the said embodiment, although the aspect which supplies a hot air from a slit nozzle was mentioned as an example as a drying means, it demonstrated and this invention is not limited to such an aspect. For example, the drying unit may be configured to be capable of supplying hot air and irradiating with an irradiation device that irradiates ultraviolet rays or electron beams. In this case, for example, a coating liquid containing an ultraviolet curable resin is applied to the substrate, hot air is supplied in the drying zone on the inlet side of the drying means to remove the solvent, and then the resin is irradiated with ultraviolet rays. A method such as curing can also be adopted.

  The coating film manufacturing apparatus 100 may further include a thickness measuring unit. It is preferable that a thickness measuring unit is disposed downstream of the drying unit 50 and connected to the control unit 24 of the manufacturing method monitoring system 20. Information relating to the coating thickness obtained by the thickness measuring means is supplied to the control means 24, and the coating film is manufactured with a desired film thickness as compared with the coating thickness stored in the control means 24. It is good also as a structure which judges. Data or a program for calculating the coating thickness based on the coating thickness obtained by the thickness measuring means may be stored in the control means 24.

[Experimental example]
Hereinafter, the present invention will be described in more detail with reference to experimental examples, but the present invention is not limited to these experimental examples.

-Preparation of coating liquid In order to manufacture the adhesive layer as a coating film, the coating liquid containing an adhesive component was prepared. Specifically, an acrylic copolymer, ethyl acetate, toluene, and methyl ethyl ketone were blended in the blending amounts shown in Table 1 to prepare three types of coating liquids A to C. The viscosity of each coating solution is as shown in Table 1. The viscosity of the coating solution was measured using an m-VROC micro sample viscometer manufactured by RheoSense.

(Experimental example 1)
The coating liquid B was coated over a length of 100 m on a long film (thickness 38 μm, width 1.3 m, polyethylene terephthalate film) using the coating liquid B as a base material to produce a coating film.
A coating liquid B having a viscosity of 2 Pa · sec was applied at a coating thickness of 153 μm. In the present experimental example, the coating thickness was calculated to be 153 μm by dividing the coating thickness of 58 μm after drying by the ratio of acrylic copolymer as the solid content of the adhesive B, 0.381.
Calculated drying time t _i, the based on the equation (2), was calculated to 68 seconds.

The applied coating liquid B was dried by the drying means 50 having the six drying zones described in the above embodiment. In this experimental example, the dry atmosphere was air.
In this experimental example, the length of each drying zone was set as follows.
First drying zone 51: 3 m
Second drying zone 52: 4.5 m
Third drying zone 53: 4.5 m
Fourth drying zone 54: 4.5 m
Fifth drying zone 55: 4.5m
Sixth drying zone 56: 4.5 m

  The mass transfer coefficient in each drying zone of this experimental example was calculated based on the formula (1), and the calculation results are shown in Table 2.

In this experimental example, the drying zone of the mass transfer coefficient _{k m} is set to ^{2.60 × 10 -2 (m / sec} ) or less, was from the first drying zone 51 to a sixth drying zone 56. Incidentally, the time from immediately after being coated with the coating means 40 until it enters the first drying zone 51, the mass transfer coefficient _{k m} is set to ^{2.60 × 10 -2 (m / sec} ) or less. A distance of 2 m was set from immediately after coating by the coating means 40 until entering the first drying zone 51.

Table 3 shows the production conditions of the coating film. As shown in Table 3, in this experimental example, the coating speed was set to 12 (m / min). It takes {2+ (3 + 4.5 × 5)} × 60/12 = 137.5 seconds (= about 138 seconds) to pass to the sixth drying zone 56 after being coated by the coating means 40. Met. Then, in this experimental example, under dry conditions the mass transfer coefficient _{k m} is set to ^{2.60 × 10 -2 (m / sec} ) or _less, the coating on the t R = 138 seconds drying substrate It is applied to the liquid.
In this experimental example, the coating liquid was dried under the condition of Δt = t _R −t _i = 138−68 = 70 seconds, and the coating film was manufactured.

Detection of defects (bubbles) was performed using an LSC-4000 series surface inspection device manufactured by MEC. In the present experimental example, bubbles having a diameter of 50 μm or more were detected by the surface inspection apparatus. The number of bubbles in the coating film according to this experimental example was four in a film having a width of 1.3 m and a length of 100 m. Table 4 shows t _R , t _i , Δt, and the number of defects.

Experimental Examples 2 to 18 were the same as in Experimental Example 1 except that the coating liquid type, coating thickness, coating speed, and mass transfer coefficient were changed to the conditions shown in Table 3. Went. Table 4 shows t _R , t _i , Δt, and the number of defects in Experimental Examples 2 to 18.
Further, the calculation result of the mass transfer coefficient k _m in each drying zone of each experimental examples shown in Table 3, shown in Tables 5 to 9. Mass transfer coefficient k _m in the first drying zone of the experimental examples 2-18 were the same as in Experimental Example 1.

FIG. 5 shows a graph showing the relationship between the number of defects in the coating film and the drying time for the coating films produced in Experimental Examples 1-18. The vertical axis (number of defects) in the graph of FIG. 5 is a logarithmic scale.
Experimental Examples 1 to 17, mass transfer coefficient _{k m} ^{is, 2.60 × 10 -2 (m /} sec) set dry conditions below, calculated dry adjusted based on the time _{t i} the coating film production conditions Made in Specifically, the mass transfer coefficient _{k m} dry set to ^{2.60 × 10 -2 (m / sec} ) or less, continuously subjected to satisfy the condition of Equation (10). As a result, according to Experimental Examples 1 to 17, the number of bubbles contained in the coating film could be reduced. Furthermore, according to Experimental Examples 1 to 16, drying is continuously performed so as to satisfy the condition of Equation (11), and the number of bubbles can be further reduced. According to Experimental Examples 1 to 15, Continuous drying is performed so as to satisfy the condition of Equation (12), and the number of bubbles can be further reduced. According to Experimental Examples 1 to 8, the condition of Equation (13) is satisfied. Continuous drying was performed and the number of bubbles could be further reduced.
On the other hand, in Example 18, for drying the mass transfer coefficient _{k m} is set to ^{2.60 × 10 -2 (m / sec} ) or less was 50 seconds, calculated dry calculated based on the equation (2) than the time t _i, or 150 seconds short, the number of bubbles contained in the coating film becomes greater than the experimental examples 1-17.

  DESCRIPTION OF SYMBOLS 11 ... Coating film, 20 ... Manufacturing method monitoring system, 21 ... Defect detection means, 22 ... Discrimination means, 23 ... Alarm means, 24 ... Control means.

Claims (2)

And drying conditions using a mass transfer coefficient k _m, which is calculated by the following equation (1), calculated drying time and t _i, be carried out in a coating film production conditions are adjusted based on the calculated by the following equation (2) The manufacturing method of the coating film characterized by these.
^{_{k m = D × (Sc /}} Pr) 0.42 × h / k a ... (1)
t _i = k _i × d × μ (2)
(In the formula (1),
k _m is the mass transfer coefficient (unit is m / sec) is,
D is the diffusion coefficient of the solvent in the gas under a dry atmosphere (unit: m ² / sec),
h is a heat transfer coefficient (unit: J / (m ² · K · sec)),
k _a is the thermal conductivity of a gas in a dry atmosphere (unit: J / (m · K · sec)),
Sc is the Schmitt number calculated by the following mathematical formula (3),
Pr is the Prandtl number calculated by the following mathematical formula (4). )
(In the formula (3),
η is the viscosity of the gas in a dry atmosphere (unit is Pa · sec),
ρ is the density of gas in a dry atmosphere (unit: kg / m ³ )
D is the diffusion coefficient (unit is m ² / sec) of the solvent in the gas in a dry atmosphere. )
(In the formula (4),
η is the viscosity of the gas in a dry atmosphere (unit is Pa · sec),
c _p is the specific heat of the gas under a dry atmosphere (in, J / (kg · K) ) is,
k _a is the thermal conductivity of a gas in a dry atmosphere (unit: J / (m · K · sec)),
In the formula (2),
t _i is the calculated drying time (unit: sec),
d is the coating thickness (unit is m);
μ is the viscosity of the coating liquid (unit is Pa · sec),
k _i = (2/9) × 10 ⁶ (the unit is (m · Pa) ⁻¹ ). ) A production method monitoring system for monitoring a production process of a coating film having a coating means and a drying means,
A defect detection means for detecting defects in the coating film;
A discriminating means for comparing the threshold value relating to the defect stored in advance with the information relating to the defect detected by the defect detecting means;
When it is determined by the determining means that the detected defect has exceeded the threshold value, the second coating film manufacturing condition not exceeding the threshold value is calculated and stored in advance. Changing from the conditions to the second coating film manufacturing conditions, and controlling means for controlling the manufacturing process of the coating film,
The coating film production conditions, and drying conditions using a mass transfer coefficient k _m, which is calculated by the following equation (1), and the calculated drying time t _i which is calculated by the following equation (2), which is adjusted based on A manufacturing method monitoring system characterized by being a condition.
^{_{k m = D × (Sc /}} Pr) 0.42 × h / k a ... (1)
t _i = k _i × d × μ (2)
(In the formula (1),
k _m is the mass transfer coefficient (unit is m / sec) is,
D is the diffusion coefficient of the solvent in the gas under a dry atmosphere (unit: m ² / sec),
h is a heat transfer coefficient (unit: J / (m ² · K · sec)),
k _a is the thermal conductivity of a gas in a dry atmosphere (unit: J / (m · K · sec)),
Sc is the Schmitt number calculated by the following mathematical formula (3),
Pr is the Prandtl number calculated by the following mathematical formula (4),
In the formula (3),
η is the viscosity of the gas in a dry atmosphere (unit is Pa · sec),
ρ is the density of gas in a dry atmosphere (unit: kg / m ³ )
D is the diffusion coefficient of the solvent in the gas under a dry atmosphere (unit: m ² / sec),
In the formula (4),
η is the viscosity of the gas in a dry atmosphere (unit is Pa · sec),
c _p is the specific heat of the gas under a dry atmosphere (in, J / (kg · K) ) is,
k _a is the thermal conductivity of a gas in a dry atmosphere (unit: J / (m · K · sec)),
In the formula (2),
t _i is the calculated drying time (unit: sec),
d is the coating thickness (unit is m);
μ is the viscosity of the coating liquid (unit is Pa · sec),
k _i = (2/9) × 10 ⁶ (the unit is (m · Pa) ⁻¹ ). )